Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add oldwinter/skills --skill agent-harness-repairgit clone --depth 1 https://github.com/oldwinter/skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/oldwinter/skills/agent-harness-repair)<a href="https://agentmods.dev/skills/oldwinter/skills/agent-harness-repair"><img src="https://agentmods.dev/badge/skills/oldwinter/skills/agent-harness-repair/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/oldwinter/skills/agent-harness-repair"><img src="https://agentmods.dev/badge/skills/oldwinter/skills/agent-harness-repair.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00165 | $0.02023 |
| Opus 5.5 | $0.00066 | $0.00809 |
| Sonnet 5.5 | $0.00033 | $0.00405 |
| Haiku 4.5 | $0.00016 | $0.00202 |
Grade B, and why
agent-harness-repair scanned grade B with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Asks for rootmediumPrivilege escalation
A mod that escalates privileges can change anything on the machine, not only the project.
- No sudo or admin escalation by default: request it only when evidence proves a permission problem a user-level install cannot fix. How it starts
The opening of the file, as written. The whole thing — 119 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Agent Harness Repair
Restore one local coding-agent CLI or harness to its last known-good state with the smallest reversible change. The command that fails today is the acceptance test: the repair is done only when that exact command passes again.
Start read-only. Diagnose before changing anything, change one layer per round, and back up every file before rewriting it.
1. Map The Harness And Install Topology
Identify which harness is broken and how it got installed before touching it.
command -v <harness>; which -a <harness> 2>/dev/null # macOS / Linux
where <harness> # Windows cmd
Get-Command <harness> -All # Windows PowerShell
<harness> --version
Record in one table:
- harness name and executable path;
- install method: native installer, package manager (npm, pnpm, yarn, brew, winget, apt), app-managed updater, or plugin/bundle runtime;
- package owner and install prefix (
npm ls -g --depth=0,pnpm list -g,brew list --versions <formula>); - current version and last known-good version;
- config/home dir
<harness-home>, log dir, and credential store path (path only, never contents); - PATH order, shims, the shell rc or profile that adds the harness, and any alias or function that shadows it.
Flag every duplicate: more than one executable on PATH, a shim next to a native binary, a second copy under another prefix, an alias or function override.
Completion criterion: the table is filled, duplicates are flagged, and the exact failing command with its before-version is recorded for the after-comparison.
2. Capture The Failure
Reproduce with the smallest real invocation: <harness> --version, the self-update command, a session start, or one tool call that triggers the hook.
For each reproduction record:
- exact command, working directory, shell/terminal, and one-shot vs interactive;
- exit code and the first error line copied verbatim;
- relevant log path and timestamp (check
<harness-home>logs and OS app log dirs); - whether the failure persists in a clean shell, another working directory, and another terminal.
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 4d ago First seen · 119 lines · 165 tokens per session scan B d9404ddb8d20
agent-harness-repair is a skill published in the GitHub repository oldwinter/skills (9 stars, last pushed 3d ago), licensed MIT. It adds 165 tokens to every session and 2,023 once invoked, about $0.0007 per session on Opus 5.5. A static security scan graded it B with 1 finding (asks for root). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-10-18.
Other skills, from other repositories
debug-optimize-lcp
Guides debugging and optimizing Largest Contentful Paint (LCP) using Chrome DevTools MCP tools. Use this skill whenever the user asks about LCP performance, slow page loads, Core Web Vitals optimization, or wants to understand why their page's main content takes too long to appear. Also use when the user mentions…
systematic-debugging
Use when debugging a failing test, build error, or runtime issue that isn't immediately obvious. Guides a 4-phase root cause analysis instead of random fix attempts.
log-error-digest
Analyze log files to troubleshoot errors, identify peak error periods, and produce error clustering, frequency statistics, and time distribution reports. Supports JSON, syslog, and Nginx formats with automatic detection. Use when a user uploads a .log file and asks to analyze errors, find patterns, debug issues, or…
deck-retro
Run a fully local agent-deck retrospective over the user's own transcripts, Recall index and logs. Use when a user wants to find recurring failures or take their own finding from investigation through synthetic reproduction, a user-filed issue, a test-first fix and contributor PR handoff. Also use for weekly usage…
incident-response-incident-response
Coordinate production incident triage, mitigation, investigation, recovery, and follow-up. Use when responding to outages or other incidents that require structured operational coordination.
cwv-optimizer
Diagnose and fix Core Web Vitals issues on AEM Edge Delivery Services pages. Goes deeper than generic CWV advice by understanding EDS-specific performance patterns including the 100KB LCP budget, E-L-D loading phases, block rendering behavior, and third-party script impact. Produces specific fixes for LCP, CLS, and…